Alternating current electric motors



1956 J. BONANNO 2;759,l13

ALTERNATING CURRENT ELECTRIC MOTORS Filed Oct. 28, 1953 TLE'QL.

66 IIHIIHHIII J 4'0 67 f a INVENTOR ATTORNEY United States Patent Ofiice2,759,113 Patented Aug. 14, 1956 ALTERNATIN G CURRENT ELECTRIC MOTORSJoseph L. Bonanno, South Orange, N. J., assignor to The LionelCorporation, New York, N. Y., a corporation of New York ApplicationOctober 28, 1953, Serial No. 388,743

7 'Claims. (Cl. Slit-=40) The present invention relates to alternatingcurrent electric motors and is more particularly directed towardelectric motors suitable for developing small output for the operationof toys.

The present invention contemplates alternating current motors having acoil, an armature arranged to be attracted in the direction axial of thecoil and having means to impart to the armature rotation about the axisof the coil.

In carrying out the present invention the armature is biased toward thecoil with a constant force, usually gravity, and a plurality ofcircumferentially disposed resilient fingers tilted in a common angulardirection to receive the load of the armature and the additional loaddue to the attraction of the armature by the coil as the flux builds up.These fingers thereupon impart a rotary impulse to the armature and,during the decay of the magnetic field, return to their normal dimensionso that upon the next increase in attractive force, they again deformand again impart rotary movement to the armature.

The accompanying drawings show, for purposes of illustrating the presentinvention, several embodiments in which the invention may take form, itbeing understood that the drawings are illustrative of the invention,rather than limiting the same.

In the accompanying drawings:

Figure 1 is a vertical, sectional view through a toy search lightemploying one form of improved motor;

Figure 2 is a top plan view of the member carrying the resilientfingers;

Figure 3 is a fragmentary sectional view at an enlarged scale on theline 3-3 of Figures 1 and 2; and

Figures 4 to 7, inclusive, are vertical, sectional views showing themodified forms of construction.

In the form of motor shown in Figure 1 the parts are secured to amagnetizable base or plate 10. This base carries a coil form 11 whichreceives a coil 12. One terminal 13 is shown as grounded to the base 10,the other lead to the coil is indicated at 14. The outer normallygrounded tubular member of a bayonet lamp socket is indicated at 15. Thesocket and base are secured together by a magnetizable tube 16. Thecenter contact of the lamp socket is indicated at 17 and is connected towire 18 with suitable power source.

The upper face 20 of the coil form 11 receives a rubber-like washer 21.This washer is provided with a plurality of circumferentially disposedrubber-like fingers 22 tilted in a common angular direction, as will beapparent from the drawings. While six fingers are shown, three or morefingers may be used.

The armature is here shown in the form of an inverted cup-shapedstamping 23 whose lower edge 24 of the armature is close to themagnetizable plate 10 so as to provide a circumferentially uniform airgap of variable length. The armature 23 has a fiat upper surface 25which rests on the resilient fingers. The armature is centered by anextension 11 of the coil form. As shown in Figure 1, the armature 23carries a bracket 26 which supports a search light housing 27. In thisconstruction the armature with the search light provides a constantgravitational force urging the armature towards the fingers 22, butinsufficient to collapse them. The air gap between the top of the cupand the socket member 15 is fixed or constant.

When the coil is energized by alternating current, the armature isattracted downwardly, thereby compressing the fingers 22 so that thesefingers, in bending down, impart an increment of turning movement to thearmature. When the magnetic field decays, the resilient fingers lift thearmature so that on the next increase in flux the operation is repeated.This will cause the armature to rotate, carrying the search light withit. A toy beacon (see Figure 7), suitable for a number of light beams,or any other load could be used instead of the search light body.

In Figure 4 the coil is indicated at 40, the coil form at 41 and amagnetizable plate is shown at 42, similar to the base plate 10 ofFigure 1. These parts are held together by a tubular member 43. The coilform 40 receives the washer 21 with fingers 22, as above described. Ashaft 44 received in the tube 43 is secured to a magnetizable armature45 similar to the armature 23. The shaft 44 carries a pinion 46 meshingwith a gear 47 mounted on a shaft 48. In this construction the tube 43is preferably non-magnetizable material and the shaft 44 is preferablyof magnetizable material, but if desired the tube 43 may be magnetizableand the shaft 44 made of non-magnetic material. This device will operateto rotate the armature in the manner above described. Here the load onthe washer is the weight of the armature, the gear 46 and the shaft 44.

Figure 5 shows a structure using substantially the same parts as inFigure 4, but mounted on a horizontal axis. The same referencecharacters are applied to the structure of Figure 5. Here the shaft 44is provided with a threaded extension 50 which receives an adjusting nut51 and coil spring 52. Here the spring tension is so adjusted as toprovide a suitable load on the rubber fingers. The unit is a selfcontained one in which the plate 42 may be secured to an extraneoussupport in any desired manner.

Figure 6 illustrates a modified form of construction utilizing the samecoil 40 and coil form 41. Here the base 60 has a flange 61 whichsupports a rubber-like disk 62 with fingers 63. The plate 60 is ofmagnetizable material and is secured to the coil form by a tube 64. Thetube 64 receives a shaft 65 which is secured to a cup shaped armaturemember 66. The armature member 66 has a flange 67 which bears on thedeformable fingers 63 and is drivingly connected with a gear 68. Thetube 64 is preferably made of non-magnetic material and the shaft 65 ofmagnetic material, but this can be reversed if desired.

The form shown in Figure 7 employs a coil 70 and coil form 71 withupwardly extending tubular guiding element 72 similar to the extension11' in Figure l. The coil form receives the rubber-like ring 73 withfingers 74 as above described. These fingers support a magnetizable disk75 which is here shown as supporting a beacon 76 adapted to emit lightbeams in two directions when a lamp bulb is carried within it.

A magnetic core member in the form of a rod 77 extends through the coilform and is secured to it and to a cup shaped magnetizable member 78,whose upper edge 79 is close to the magnetizable armature 75.

It will be understood that while the units shown in Figures 6 and 7 areillustrated in a form of construction suitable for using gravity as thebiasing force for the armature, that these units can be constructed foroperation on a horizontal axis by utilizing constructions sary tooperate beacons, search lights. and other toyv on exhibition deviceswhere; small torque: andrelatively'lowspeeds: is required The magnetic;circuitstshown herein are-very efli'cient due tothe use of arigid:armature andthe employment-ofia-ifixed and a variable air-gap;

Since it is obvious that the invention maybe embodied in. other formsand constructions: within thescope of the! claims, I wish it to heunderstood that the particular formssshowmherein are-but several oftheseforrns, and;

various modifications and" changes being: possible, I do. not; otherwiselimit: myself in any way. with respectthereto;

What: is claimed is:

13 An electric-motor comprising a-coil, a magnetizable' corerin thecoil; a magnetizable plate atone end ofi the coil, aamagnetizable cupwhich receivestheacoilland has its peripheral edge adjacent the plate toprovide amarrowvariable air; gap, means: to fixedly secure one: of thesecond:and' thirdimentioned magnetizable elements to the coil, means :tomount the otherof'said second? and third' magnetizable elements forrotation about the axis of the coil andafonmovement in an, axialdirection with fixed 'air gap with respectzto the core, and aresilientmember'between the coiland the rotatable'elementandprovidedwith circumferentially: disposed resilientfingers tilted in a commondirection and depressableupon building up -of magnetic flux to imparta-- turning movement tothe rotatable part.

2'. An alternating current motor comprising a-- coilfonm, a-coil carriedby the coil form, a magnetizable core extending through the-coil, amagnetizable disk carried at one=end" of the-coilform, a magnetizablecup-about-the 4. E coil, form, with. itsedge spaced from, the disk to:form a variable air gap, one of the variable air gap formingmagnetizable parts beingfixed relative-t0 the coilform, the other beingmovable, the closed end of the cup being adjacent the other end of thecoil form and at a substantially constant distance from the coil to forman air gap of substantially constant length, means biasing the cuptoward the disk with a constant force to shorten the variable air gap,and a ring of rubber-like material provided. with a plurality ofcircumferentially disposed resilient fingers tiltedin a common angulardirection,.the fingers being disposed in a position relative. to the.coil axis to assume said force and to be distorted when the magnetizableparts are attracted toward one another and thereby impart turningmovement tothe armature with increase of magnetic flow and adapted toregain their normal position with decay of the magnetic field.

3. The alternating current motor of claim 2 wherein the coil axis isvertical and the armature is gravity biased;

42-v An alternating current motor asclaimed'in claim 2;

wherein-the resilientfingers. are disposed inva position to bear againstthe closed end of thev cup.

5; Arr-,alternatingcurrent motor as claimed in claim 2,

wherein; the resilient. fingers are disposed between' the periphery. ofthe; cup. and the disk.

6, Anra-lternating,currentmotor as claimed in claim 2,

wherein the cup forms the movable armature and thedislo: isr.fixed; to.the coilform.

7'. An alternatingcurrent motor as'lclaimed in claim i2,

whereinthercupis fixed to. the coil form and the disle is movable..-

Referencesflited in the file ofthispatent UNITED STATES PATENTS 827,590Rittenhouse Oct. 13,1931, 1,83'6;748T Carley .Dec. 15, 1931.

